High-CRI White Light Source Using Blue Laser and Red Spectral Mixing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing white light sources using laser diodes and phosphors face inefficiencies, particularly with diode lasers emitting at 620 nm being inefficient, and struggle to achieve high intensity with high color rendering index (CRI) and low correlated color temperature (CCT) simultaneously.
Innovation Solution
A light generating device comprising a blue laser source, a Ce-doped garnet luminescent material converting blue light into green and yellow, and a red laser source, optimized to produce white light with a CRI of at least 75 and CCT between 2000-4000 K, using specific wavelength ranges for each light source to achieve efficient color temperature and rendering index.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If a laser diode and phosphor combination is used to generate white light, then high intensity can be achieved, but the color rendering index (CRI) and correlated color temperature (CCT) control are insufficient
Solution Approach 1:
The invention segments the white light generation into multiple independent light sources with specific wavelengths (blue LED at 440-475 nm, amber LED at 580-610 nm, red LED at 625-670 nm) instead of using a single phosphor-converted laser. Each wavelength component can be independently controlled to achieve precise color rendering while maintaining high intensity through the combined output of multiple sources.
Solution Approach 2:
The invention uses a composite approach by combining multiple LED light sources with different spectral characteristics to create a unified white light output. This composite light source integrates the advantages of each wavelength range (blue for brightness, amber for warmth, red for color rendering) to simultaneously achieve high intensity and high CRI with controllable CCT.
2Reliability
If multiple light sources are combined to improve CRI and CCT control, then color rendering quality improves, but device complexity increases
Solution Approach 1:
The invention merges multiple LED light sources into a single integrated device housing, where the blue, amber, and red LEDs are positioned in close proximity with their respective phosphor materials. This merging approach allows the complex multi-wavelength system to function as a unified light generating device, simplifying the overall structure while maintaining the ability to control CRI and CCT through coordinated operation of the integrated components.
3Reliability
If specific wavelength ranges are used for each light source to achieve high CRI, then color rendering index improves, but energy efficiency may deteriorate
Solution Approach 1:
The invention optimizes the specific wavelength parameters of each LED source (blue: 440-475 nm, amber: 580-610 nm, red: 625-670 nm) to achieve maximum color rendering efficiency. By carefully selecting these wavelength ranges and matching them with appropriate phosphor materials, the system maximizes the luminous efficacy of each wavelength component, ensuring that energy is converted to visible light in the most efficient manner while achieving high CRI values.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The device provides high-intensity white light with a broad range of correlated color temperatures and high color rendering indices, including low CCT values, by combining blue, green-yellow, and red light sources, enhancing efficiency and color accuracy.
Implementation Method 1
The first luminescent material is configured to convert at least part of the first light source light into first luminescent material light having an emission band having wavelengths in one or more of (a) the green spectral wavelength range and (b) the yellow spectral wavelength range
Data Source
Figure 1A~1B
Figure 1C~1D
Figure 1E~1F
AI summary
The invention provides a light generating device (1000) configured to generate device light (1001), wherein the light generating device (1000) comprises a first light source (110), a first luminescent material (210), a second source (120) of second light (121), and a third light source (130), wherein: the first light source (110) is configured to generate blue first light source light (111) having a first peak wavelength λι selected from the spectral wavelength range of 440- 475 nm, wherein the first light source (110) is a first laser light source (10); the first luminescent material (210) is configured to convert at least part of the first light source light (111) into first luminescent material light (211) having an emission band having wavelengths in one or more of (a) the green spectral wavelength range and (b) the yellow spectral wavelength range, wherein the first luminescent material (210) comprises a luminescent material of the type A3B5O12:Ce, wherein A comprises one or more of Y, Gd, Tb and Lu, and wherein B comprises one or more of Al, Ga, and In, wherein A comprises at least Y, and wherein B comprises at least Al; the second source (120) of second light (121) is configured to provide the second light (121) having an emission band having a dominant wavelength or peak wavelength in the spectral wavelength range of 580-610 nm; the third light source (130) is configured to generate red third light source light (131) having a third peak wavelength λ3 selected from the spectral wavelength range of 630- 670 nm, wherein the third light source (130) is a third laser light source (30); the light generating device (1000) is configured to provide in a first operational mode white device light (1001) comprising the first light source light (111), the first luminescent material light (211), the second light (121), and the third light source light (131), with a correlated color temperature selected from the range of 2000-5000 K and a color rendering index (CRI) of at least 80.